package com.jjlin.leetcode;

class Solution21 {
    public ListNode mergeTwoLists(ListNode l1, ListNode l2) {
        ListNode head = new ListNode(-1);
        ListNode cur = head;
        while(l1 != null && l2 != null){
            if(l1.val < l2.val){
                cur.next = l1;
                l1 = l1.next;
            }else{
                cur.next = l2;
                l2 = l2.next;
            }
            cur = cur.next;
        }
        if(l1 != null)
            cur.next = l1;
        if(l2 != null)
            cur.next = l2;
        return head.next;
    }
}
